You don't need a passport for him but make sure that you have a signed and notarized statement from the parents stating that you have their permmision to take him out of the country. The signed and notarized statement should also give you full authority to make all decisions for the child's health and well-being during the period of time you will be gone. This is very important--only lifesaving medical treatment can be rendered to a child without parental permission. If there is a minor accident or illness, you do not want the child to have to wait for treatment while you try to track down the parents.